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/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
/* double gamma(double x)
* Return the logarithm of the Gamma function of x or the Gamma function of x,
* depending on the library mode.
*/
#include "math.h"
#include "math_private.h"
double tgamma(double x)
{
double y;
int local_signgam;
y = __ieee754_gamma_r(x, &local_signgam);
if (local_signgam < 0)
y = -y;
#ifndef _IEEE_LIBM
if (_LIB_VERSION == _IEEE_)
return y;
if (!isfinite(y) && isfinite(x)) {
if (floor(x) == x && x <= 0.0)
return __kernel_standard(x, x, 41); /* tgamma pole */
return __kernel_standard(x, x, 40); /* tgamma overflow */
}
#endif
return y;
}
libm_hidden_def(tgamma)
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